Photocurrent detection device and system
By providing a photocurrent detection device, the problem of photocurrent detection delay in wafer development was solved, enabling fast and low-cost photocurrent detection and reducing the delay in finished product packaging.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-20
- Publication Date
- 2026-03-20
AI Technical Summary
During the wafer development phase, photocurrent detection requires repeated testing of numerous process conditions, leading to delays in product development and increased costs.
A photocurrent detection device is provided, comprising a light source module, a photocurrent detection module, and a power supply module, for directly detecting photocurrent during the wafer fabrication and R&D stage, thereby reducing the delay and cost of finished product packaging.
It enables rapid photocurrent detection during the wafer fabrication and R&D phase, reducing development delays and lowering costs.
Smart Images
Figure CN224022239U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wafer testing technology, and in particular to a photocurrent detection device and system. Background Technology
[0002] In photosensitive devices, photocurrent is a crucial indicator of their photosensitivity; a higher photocurrent generally indicates greater sensitivity. Therefore, after photosensitive device packaging, photocurrent testing is typically performed to determine if the photocurrent meets specifications. However, during the wafer development phase, numerous trials of various process conditions are usually required to achieve the desired photocurrent. Testing each process condition after packaging into a finished product according to a standard procedure would significantly delay product development and increase costs. Utility Model Content
[0003] Therefore, it is necessary to provide a photocurrent detection device and system.
[0004] In a first aspect, this application provides a photocurrent detection device, comprising:
[0005] A light source module is used to provide a target beam for the wafer under test; wherein, the standard wafer corresponding to the wafer under test generates a photocurrent of a preset value under the illumination of the target beam.
[0006] A photocurrent detection module, connected to the wafer under test, is used to detect the photocurrent generated by the wafer under test under the illumination of the target beam;
[0007] The power supply module is connected to the light source module and the photocurrent detection module respectively, and is used to provide a first power supply voltage to the light source module and a second power supply voltage to the photocurrent detection module respectively.
[0008] In one embodiment, the light source module includes:
[0009] A light source, connected to the power module, is used to provide a light beam under the action of the first power supply voltage;
[0010] An intensity adjustment unit, connected to the light source, is used to adjust the illumination intensity of the light beam to provide the target light beam to the wafer under test.
[0011] In one embodiment, the light source module further includes:
[0012] A power supply current display unit, connected to the light source and the power module, is used to acquire and display the current of the light source; wherein,
[0013] When the current of the light source reaches a preset power supply current value, the light source provides the target beam;
[0014] The photocurrent detection module is used to detect the photocurrent of the wafer under test when the current value displayed by the power supply current display unit is a preset power supply current value.
[0015] In one embodiment, the light intensity adjustment unit includes an adjustable resistor connected to the light source and the power module, respectively.
[0016] In one embodiment, the photocurrent detection device further includes a light source adjustment component connected to the adjustable resistor, which is used to adjust the resistance value of the adjustable resistor to change the illumination intensity of the light beam, so that the wafer under test provides the target light beam.
[0017] In one embodiment, the photocurrent detection device further includes a light source interface for connecting to the light source.
[0018] In one embodiment, the photocurrent detection device further includes a photosensitive interface for connecting to the wafer under test.
[0019] In one embodiment, the power module includes:
[0020] A first power source is connected to the light source module and is used to provide a first power supply voltage to the light source module;
[0021] The second power source is used to provide AC voltage;
[0022] An AC-DC conversion unit is connected to the second power supply and the photocurrent detection module, respectively, and is used to convert the AC voltage into the second power supply voltage.
[0023] In one embodiment, the photocurrent detection device further includes:
[0024] A switching module is connected to the power supply module, the light source module, and the photocurrent detection module, respectively, and is used to select and connect the connection path between the power supply module and the light source module, and to select and connect the connection path between the power supply module and the photocurrent detection module.
[0025] Secondly, this application also provides a photocurrent detection system, including a wafer under test and a photocurrent detection device provided in any of the above embodiments.
[0026] In the aforementioned photocurrent detection device and system, the photocurrent detection device includes a light source module, a photocurrent detection module, and a power supply module. The power supply module provides a first power supply voltage to the light source module and a second power supply voltage to the photocurrent detection module. The light source module provides a target beam to the wafer under test under the first power supply voltage, and the photocurrent detection module detects the photocurrent generated by the wafer under test under the target beam illumination under the second power supply voltage. The photocurrent detection device of this application is small in size and easy to move, enabling the detection of wafer photocurrent during the wafer manufacturing and R&D stage, reducing development delays caused by finished product packaging and lowering development costs. Attached Figure Description
[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 This is a schematic diagram of the structure of a photocurrent detection device according to one embodiment;
[0029] Figure 2 This is a schematic diagram of the structure of a light source module provided in one embodiment;
[0030] Figure 3 An equivalent circuit diagram of a light source module provided in one embodiment;
[0031] Figure 4 This is a package diagram of a photocurrent detection device according to a specific embodiment;
[0032] Figure 5 This is a schematic diagram of the structure of a photocurrent detection device according to another embodiment.
[0033] Explanation of reference numerals in the attached figures:
[0034] 100-Light source module, 110-Light source, 120-Light source adjustment unit, 130-Power supply current display unit, 200-Photocurrent detection module, 210-Display unit, 300-Power supply module, 310-First power supply, 320-Second power supply, 330-AC-DC conversion unit, 400-Light source adjustment component, 510-First light source interface, 520-Second light source interface, 610-First photosensitive interface, 620-Second photosensitive interface, 700-Switch module. Detailed Implementation
[0035] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.
[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0037] It is understood that the terms "first," "second," etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first interface may be referred to as a second interface, and similarly, a second interface may be referred to as a first interface. Both the first interface and the second interface are interfaces, but they are not the same interface.
[0038] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.
[0039] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.
[0040] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.
[0041] In one embodiment, this application provides a photocurrent detection device, such as... Figure 1 As shown, it includes a light source module 100, a photocurrent detection module 200, and a power supply module 300. The power supply module 300 is connected to both the light source module 100 and the photocurrent detection module 200.
[0042] The light source module 100 provides a target beam to the wafer under test 400. The standard wafer corresponding to the wafer under test generates a photocurrent of a preset value under the illumination of the target beam. The standard wafer is a wafer that meets the photocurrent design requirements. The preset photocurrent value is the maximum photocurrent value that the user requires or expects the wafer under test to generate under the illumination of the target beam.
[0043] The photocurrent detection module 200 is connected to the wafer under test 400 and can be used to detect the photocurrent generated on the wafer under test 400 under the illumination of a target beam. Since the photocurrent is very small, the detection accuracy of the photocurrent detection module 200 is required to be high. For example, the photocurrent detection module 200 can have a measurement range of 20 microamps to 100 microamps and a minimum resolution of 10 nanoamps. Furthermore, after detecting the photocurrent, the photocurrent detection module 200 can also display the photocurrent value. For example, the display unit 210 of the photocurrent detection module can be a digital display unit or a magnetoelectric needle ammeter.
[0044] The power supply module 300 provides a first power supply voltage to the light source module 100 and a second power supply voltage to the photocurrent detection module 200. The first power supply voltage and the second power supply voltage can be the same or different. For example, the first power supply voltage can be 3.7V or 7.4V, and the second power supply voltage can be 5V; optionally, both the first power supply voltage and the second power supply voltage can be 5V.
[0045] In this embodiment, the photocurrent detection device includes a light source module 100, a photocurrent detection module 200, and a power supply module 300. The power supply module 300 provides a first power supply voltage to the light source module 100 and a second power supply voltage to the photocurrent detection module 200. The light source module 100 provides a target beam to the wafer under test 400 under the first power supply voltage, and the photocurrent detection module 200 detects the photocurrent generated by the wafer under test 400 under the illumination of the target beam under the second power supply voltage. The photocurrent detection device of this application is small in size, easy to move, and low in cost. It can detect the photocurrent of a wafer during the wafer manufacturing and R&D stage, reducing development delays caused by finished product packaging and lowering development costs.
[0046] In one embodiment, such as Figure 2 As shown, the light source module 100 includes a light source 110 and a light intensity adjustment unit 120. The light source 110 is connected to the power supply module 300 and the light intensity adjustment unit 120, respectively.
[0047] The light source 110 can be used to provide a light beam under the action of a first supply voltage. In order to improve the detection accuracy, the light source 110 needs to provide a stable and fluctuation-free light beam. The light source 110 can be a photodiode that emits a light beam of a specific wavelength, such as an infrared diode that emits a light beam of 940 nanometer wavelength.
[0048] The intensity adjustment unit 120 can be used to adjust the illumination intensity of the light beam to provide a target light beam for the wafer under test. Furthermore, the intensity adjustment unit 120 includes an adjustable resistor, which is connected to the light source 110 and the power supply module 300, respectively. The equivalent circuit diagram of the light source module 100 is shown below. Figure 3 As shown, it can be understood that by adjusting the resistance value of the adjustable resistor, the current value flowing through the light source 110 can be changed, thereby changing the light intensity of the light beam emitted by the light source 110, so that the light source 110 can provide the target light beam.
[0049] In one embodiment, such as Figure 4 As shown, the photocurrent detection device also includes a light source adjustment component 400. The light source adjustment component 400 is connected to an adjustable resistor and is used to adjust the resistance value of the adjustable resistor to change the illumination intensity of the light beam, so that the light source 110 can provide a target light beam to the wafer under test. The light source adjustment component 400 can be a mechanical knob or a touch screen, etc. The resistance value of the adjustable resistor can be changed by rotating the mechanical knob, or by inputting a target resistance value through the touch screen.
[0050] In one embodiment, such as Figure 4 As shown, the light source module 100 also includes a power supply current display unit 130. The power supply current display unit 130 is connected to both the light source 110 and the power module 300, and can be used to acquire and display the current of the light source 110. Specifically, when the current of the light source 110 reaches a preset power supply current value, the light source 110 provides the target beam. The preset power supply current value is the light source current corresponding to when the photocurrent generated by the standard wafer reaches the preset photocurrent value.
[0051] The photocurrent detection module 200 is used to detect the photocurrent of the wafer under test when the current value displayed by the power supply current display unit 130 is a preset power supply current value. It can be understood that when the current value displayed by the power supply current display unit 130 is the preset power supply current value, the photocurrent value detected by the photocurrent detection module 200 can be compared with the preset photocurrent value to determine whether the photocurrent of the wafer under test meets the standard, thus eliminating errors caused by differences in the illumination intensity of the light beam.
[0052] In one embodiment, such as Figure 4As shown, the photocurrent detection device also includes a light source interface for connecting to a light source. The number of light source interfaces can be reasonably set based on the type of light source used. Taking an LED lamp as an example, the light source interface may include a first light source interface 510 and a second light source interface 520. The first light source interface 510 and the second light source interface 520 can be used to connect to the anode and cathode of the LED lamp respectively.
[0053] In one embodiment, such as Figure 4 As shown, the photocurrent detection device also includes a photosensitive interface for connecting to the wafer under test. The photosensitive interface includes a first photosensitive interface 610 and a second photosensitive interface 620, which can be connected to the two electrodes of the wafer under test one-to-one. Specifically, when the wafer under test is a two-terminal device, the first photosensitive interface 610 and the second photosensitive interface 620 can be connected to the two electrodes of the wafer under test one-to-one; when the wafer under test is a three-terminal device, the first photosensitive interface 610 and the second photosensitive interface 620 can be connected to the source and drain electrodes of the wafer under test one-to-one.
[0054] In one embodiment, such as Figure 5 As shown, the power module 300 includes a first power supply 310, a second power supply 320, and an AC-DC conversion unit 330.
[0055] The first power supply 310 is connected to the light source module 100 and can be used to provide a first power supply voltage to the light source module 100. The first power supply 310 can be a lithium battery, a linear power supply, or a constant current source, etc. Using the first power supply 310 can provide a stable DC voltage to the light source module 100, which can further improve the stability of the beam emitted by the light source module.
[0056] The AC-DC conversion unit 330 is connected to the second power supply 320 and the photocurrent detection module 200, respectively. The second power supply 320 can be used to provide AC voltage, and the AC-DC conversion unit 330 is used to convert the AC voltage into a second supply voltage. For example, the AC voltage can be 220V AC voltage.
[0057] In one embodiment, such as Figure 4 As shown, the photocurrent detection device also includes a switch module 700. The switch module 700 is connected to the power supply module 300, the light source module 100, and the photocurrent detection module 200, respectively, and is used to select the connection path between the power supply module 300 and the light source module 100, and to select the connection path between the power supply module 300 and the photocurrent detection module 200. The switch module 700 can be a push-button switch or a key switch, etc.
[0058] In one embodiment, this application also provides a photocurrent detection system, which may include a wafer under test and a photocurrent detection device provided in any of the above embodiments.
[0059] The following describes the process of using the photocurrent detection device of this application to detect a wafer under test, including the calibration process and the detection process, using a specific embodiment.
[0060] The calibration process is as follows: Place a standard wafer with a known photocurrent on a wafer stage, and make contact between the probes on the wafer stage and the electrodes on the front side of the standard wafer. Connect the first photosensitive interface 610 and the second photosensitive interface 620 in the photocurrent detection device to the electrodes on the front and back sides of the standard wafer, respectively. Press the switch module 700 to turn on the light source 110, and change the resistance value of the adjustable resistor through the light source adjustment component 400 to change the light intensity of the light beam provided by the light source 110. When the photocurrent detected by the photocurrent detection module 200 reaches the preset photocurrent value (which can be visually seen through the display unit 210), record the current value displayed by the power supply current display unit 130 as the preset power supply current value, thus completing the calibration.
[0061] The testing procedure is as follows: Place the wafer under test on the wafer stage, with the probes on the stage contacting the electrodes on the front side of the wafer. Connect the first photosensitive interface 610 and the second photosensitive interface 620 of the photocurrent detection device to the front and back electrodes of the wafer, respectively. Press the switch module 700 to turn on the light source 110. When the current value displayed by the power supply current display unit 130 is the preset power supply current value, record the photocurrent detected by the photocurrent detection module 200 (which can be visually viewed through the display unit 210), thus completing the test.
[0062] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.
[0063] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0064] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.
Claims
1. A photocurrent detection device, characterized in that, include: A light source module is used to provide a target beam for the wafer under test; wherein, the standard wafer corresponding to the wafer under test generates a photocurrent of a preset value under the illumination of the target beam. A photocurrent detection module, connected to the wafer under test, is used to detect the photocurrent generated by the wafer under test under the illumination of the target beam; The power supply module is connected to the light source module and the photocurrent detection module respectively, and is used to provide a first power supply voltage to the light source module and a second power supply voltage to the photocurrent detection module respectively.
2. The photocurrent detection device according to claim 1, characterized in that, The light source module includes: A light source, connected to the power module, is used to provide a light beam under the action of the first power supply voltage; An intensity adjustment unit, connected to the light source, is used to adjust the illumination intensity of the light beam to provide the target light beam to the wafer under test.
3. The photocurrent detection device according to claim 2, characterized in that, The light source module also includes: A power supply current display unit, connected to the light source and the power module, is used to acquire and display the current of the light source; wherein, When the current of the light source reaches a preset power supply current value, the light source provides the target beam; The photocurrent detection module is used to detect the photocurrent of the wafer under test when the current value displayed by the power supply current display unit is a preset power supply current value.
4. The photocurrent detection device according to claim 2, characterized in that, The light intensity adjustment unit includes an adjustable resistor, which is connected to the light source and the power module respectively.
5. The photocurrent detection device according to claim 4, characterized in that, The photocurrent detection device further includes a light source adjustment component, which is connected to the adjustable resistor and is used to adjust the resistance value of the adjustable resistor to change the illumination intensity of the light beam, so that the wafer under test provides the target light beam.
6. The photocurrent detection device according to claim 2, characterized in that, The photocurrent detection device also includes a light source interface for connecting to the light source.
7. The photocurrent detection device according to any one of claims 1-6, characterized in that, The photocurrent detection device also includes a photosensitive interface, which is used to connect to the wafer under test.
8. The photocurrent detection device according to any one of claims 1-6, characterized in that, The power module includes: A first power source is connected to the light source module and is used to provide a first power supply voltage to the light source module; The second power source is used to provide AC voltage; An AC-DC conversion unit is connected to the second power supply and the photocurrent detection module, respectively, and is used to convert the AC voltage into the second power supply voltage.
9. The photocurrent detection device according to claim 1, characterized in that, The photocurrent detection device further includes: A switching module is connected to the power supply module, the light source module, and the photocurrent detection module, respectively, and is used to select and connect the connection path between the power supply module and the light source module, and to select and connect the connection path between the power supply module and the photocurrent detection module.
10. A photocurrent detection system, characterized in that, It includes the wafer to be tested and the photocurrent detection device as described in any one of claims 1-9.